Theaetetus (crater)

Theaetetus
	LRO image
Coordinates	37°00′N6°00′E / 37.0°N 6.0°E Coordinates: 37°00′N6°00′E / 37.0°N 6.0°E
Diameter	25 km
Depth	2.8 km
Colongitude	354° at sunrise
Eponym	Theaetetus

Last updated August 08, 2019

Theaetetus is a lunar impact crater that is located to the southeast of the crater Cassini near the eastern edge of Mare Imbrium. It was named after the ancient Greek mathematician Theaetetus.^[1] It lies just to the west of the Montes Caucasus range, which forms the eastern shore of the mare. To the southwest is the prominent crater Aristillus.

Lunar craters are impact craters on Earth's Moon. The Moon's surface has many craters, almost all of which were formed by impacts.

An impact crater is an approximately circular depression in the surface of a planet, moon, or other solid body in the Solar System or elsewhere, formed by the hypervelocity impact of a smaller body. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Impact craters range from small, simple, bowl-shaped depressions to large, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth.

Cassini is a lunar impact crater that is located in the Palus Nebularum, at the eastern end of Mare Imbrium. The crater was named after astronomers Giovanni Cassini and Jacques Cassini. To the northeast is the Promontorium Agassiz, the southern tip of the Montes Alpes mountain range. South by south-east of Cassini is the crater Theaetetus. To the northwest is the lone peak Mons Piton.

The rim of Theaetetus is distinctly polygonal in shape, with a slight rounding at the vertices. There is a low outer rampart and a slight central rise on the crater floor, which is offset to the northeast of the crater midpoint. The interior is otherwise relatively featureless.

In elementary geometry, a polygon is a plane figure that is described by a finite number of straight line segments connected to form a closed polygonal chain or polygonal circuit. The solid plane region, the bounding circuit, or the two together, may be called a polygon.

Theaetetus crater taken from Earth in 2012 at the University of Hertfordshire's Bayfordbury Observatory with the telescopes Meade LX200 14" and Lumenera Skynyx 2-1 Theaetetus lunar crater map.jpg — Theaetetus crater taken from Earth in 2012 at the University of Hertfordshire's Bayfordbury Observatory with the telescopes Meade LX200 14" and Lumenera Skynyx 2-1

This crater has been noted in the past as a site of possible transient lunar phenomena. In 1902, a white cloud was observed briefly in the vicinity of the crater. Other observers, including Patrick Moore and W. H. Pickering, have also noted unusual appearances in this area.

Transient lunar phenomenon short-lived light, color, or change in appearance on the surface of the Moon

A transient lunar phenomenon (TLP) or lunar transient phenomenon (LTP) is a short-lived light, color, or change in appearance on the surface of the Moon.

Sir Patrick Alfred Caldwell-Moore was an English amateur astronomer who attained prominent status in that field as a writer, researcher, radio commentator and television presenter.

William Henry Pickering was an American astronomer. Pickering constructed and established several observatories or astronomical observation stations, notably including Percival Lowell's Flagstaff Observatory. He led solar eclipse expeditions and studied craters on the Moon, and hypothesized that changes in the appearance of the crater Eratosthenes were due to "lunar insects". He spent much of the later part of his life at his private observatory in Jamaica.

Related Research Articles

Deseilligny is a small lunar impact crater in the southern part of the Mare Serenitatis. It was named after French selenographer Jules Deseilligny. It is located to the east-southeast of the crater Bessel. Deseilligny is a bowl-shaped crater with a low rim. It is otherwise undistinguished.

Finsch is a relatively small lunar impact crater in the mid-part of Mare Serenitatis that has been almost completely covered by the mare, forming a ghost crater in the lava plain. It was named after German zoologist Otto Finsch. It is located to the south-southeast of the crater Sarabhai and northeast of Bessel.

Amontons is a tiny lunar impact crater in the western half of the Mare Fecunditatis. It is a circular, cup-shaped formation that has been excavated out of the level surface by the impact, and is the same dark hue as the surrounding mare. When the sun is at a low angle, multiple ghost-craters are visible in the mare surface to the south-southeast and north of it.

Bombelli is a small lunar impact crater that is located in the highlands to the north of the Sinus Successus. It was named after Italian mathematician Raphael Bombelli. It was previously designated Apollonius T. The crater Apollonius is located to the east-southeast.

Carrel is a small lunar crater on the Mare Tranquillitatis. It has a somewhat distorted appearance, having a slight protruding bulge in the northwest rim. The interior is somewhat irregular, with ridges and some slumped material. This crater lies across a ridge in the surface of the mare.

Euler is a lunar impact crater located in the southern half of the Mare Imbrium, and is named after the Swiss mathematician, physician and astronomer Leonhard Euler. The most notable nearby feature is Mons Vinogradov to the west-southwest. There is a cluster of low ridges to the southwest, and this formation includes the small crater Natasha and the tiny Jehan. About 200 kilometers to the east-northeast is the comparably sized crater Lambert.

Aristillus is a prominent lunar impact crater that lies in the eastern Mare Imbrium. It was named after Greek astronomer Aristyllus. Directly to the south is the smaller crater Autolycus, while to the southwest is the large Archimedes. To the northeast are the craters Theaetetus and Cassini.

Doppelmayer is the remains of a lunar impact crater that lies on the southwest edge of Mare Humorum. It was named after the German mathematician and astronomer Johann Gabriel Doppelmayr. To the south-southeast is another flooded crater designated Lee, and to the southeast is Vitello. Just to the east-northeast of Doppelmayer lies the nearly submerged crater Puiseux.

Archytas is a lunar impact crater that protrudes into the northern edge of Mare Frigoris. To the northwest is the comparably sized crater Timaeus, and the smaller Protagoras lies in the opposite direction to the southeast. Further to the southwest, beyond the opposite edge of the mare, is the dark-floored crater Plato.

Calippus is a small lunar impact crater that is located on the eastern edge of the rugged Montes Caucasus mountain range in the northern part of the Moon. It was named after Greek astronomer Callippus of Cyzicus. It lies to the southwest of the crater remnant Alexander, to the northwest of the Mare Serenitatis.

Belyaev is a lunar impact crater that is attached to the outer edge of the Mare Moscoviense, on the far side of the Moon. It is a worn formation with a small crater pair overlaying the southern rim, and several smaller craters across the relatively irregular interior.

Bouguer is a lunar impact crater that lies along the southern edge of the Mare Frigoris, to the north of the crater Bianchini. To the west-southwest of Bouguer, along the same shore of the mare, is the crater Foucault. Nearly due west is the more prominent Harpalus, and to the west is La Condamine.

Brunner is a lunar impact crater that is located along the eastern limb of the Moon, to the southeast of the Mare Smythii. At this location the crater is viewed from the edge, and so it is not possible to see much detail from the Earth. The visibility of this formation is also affected by libration. The crater lies to the southwest of the walled plain Hirayama, and to the east of the elongated crater Houtermans.

Elmer is a small lunar impact crater that is located to the south of Mare Smythii, near the eastern limb of the Moon. This crater is seen at a highly oblique angle from Earth, and the visibility is affected by libration. Elmer lies southwest of the crater Kreiken, and east-southeast of the larger Dale. This is a circular, bowl-shaped crater with an interior floor that occupies about half the total diameter.

Chant is a lunar impact crater that is located on the far side of the Moon, behind the southwest limb as seen from the Earth. It lies within the southwestern part of the blanket of ejecta surrounding the Mare Orientale, beyond the Montes Cordillera mountain ring. To the west-northwest is the large walled plain Blackett. Southward is the crater Mendel.

Courtney is a tiny lunar impact crater on the Mare Imbrium, a lunar mare in the northwest quadrant of the Moon. It lies about two crater diameters to the northwest of Euler, in an otherwise isolated stretch of the mare. The dark surface in this region is marked by Euler's ray material. The name is an English male name.

Chadwick is a lunar impact crater that lies on the far side of the Moon's surface, just beyond the southwestern limb. It is located to the northwest of the crater De Roy, and was previously designated De Roy X before being given its current name by the IAU. This region of the lunar surface lies at the southern end of the ejecta blanket that surrounds the Mare Orientale impact basin.

Eichstadt is a lunar impact crater that is located in the eastern section of the Montes Cordillera range that encircles the Mare Orientale impact basin. It lies toward the southwestern limb of the Moon, and so appears oblong when viewed from the Earth due to foreshortening. Over 200 kilometers to the east of Eichstadt are the craters Darwin and Lamarck, and to the south is Krasnov.

Feoktistov is a small lunar impact crater on the far side of the Moon. It lies in the northern hemisphere, to the northwest of the Mare Moscoviense. This crater has a small outward extension along the northern side, giving it the appearance of two overlapping craters that have merged. There are slight indentations of the rim along the east and northwest sides. The rim is otherwise rounded and not significantly worn. Apart from an irregular strip in the northeast, the floor is relatively featureless.

References

↑ "Theaetetus (crater)" . Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.

Andersson, L. E.; Whitaker, E. A. (1982). NASA Catalogue of Lunar Nomenclature. NASA RP-1097.
Bussey, B.; Spudis, P. (2004). The Clementine Atlas of the Moon. New York: Cambridge University Press. ISBN 978-0-521-81528-4.
Cocks, Elijah E.; Cocks, Josiah C. (1995). Who's Who on the Moon: A Biographical Dictionary of Lunar Nomenclature. Tudor Publishers. ISBN 978-0-936389-27-1.
McDowell, Jonathan (July 15, 2007). "Lunar Nomenclature". Jonathan's Space Report . Retrieved 2007-10-24.
Menzel, D. H.; Minnaert, M.; Levin, B.; Dollfus, A.; Bell, B. (1971). "Report on Lunar Nomenclature by the Working Group of Commission 17 of the IAU". Space Science Reviews. 12 (2): 136–186. Bibcode:1971SSRv...12..136M. doi:10.1007/BF00171763.
Moore, Patrick (2001). On the Moon. Sterling Publishing Co. ISBN 978-0-304-35469-6.
Price, Fred W. (1988). The Moon Observer's Handbook. Cambridge University Press. ISBN 978-0-521-33500-3.
Rükl, Antonín (1990). Atlas of the Moon. Kalmbach Books. ISBN 978-0-913135-17-4.
Webb, Rev. T. W. (1962). Celestial Objects for Common Telescopes (6th revised ed.). Dover. ISBN 978-0-486-20917-3.
Whitaker, Ewen A. (1999). Mapping and Naming the Moon. Cambridge University Press. ISBN 978-0-521-62248-6.
Wlasuk, Peter T. (2000). Observing the Moon. Springer. ISBN 978-1-85233-193-1.

Ewen Adair Whitaker was a British-born astronomer who specialized in lunar studies. During World War II he was engaged in quality control for the lead sheathing of hollow cables strung under the English Channel as part of the "Pipe Line Under The Ocean" Project (PLUTO) to supply gasoline to Allied military vehicles in France. After the war, he obtained a position at the Royal Greenwich Observatory working on the UV spectra of stars, but became interested in lunar studies. As a sideline, Whitaker drew and published the first accurate chart of the South Polar area of the Moon in 1954, and served as director of the Lunar Section of the British Astronomical Association.

The National Aeronautics and Space Administration is an independent agency of the United States Federal Government responsible for the civilian space program, as well as aeronautics and aerospace research.

Ben J. Bussey is an American planetary scientist.

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[1] "Theaetetus (crater)" . Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.

LRO image
Coordinates	37°00′N6°00′E / 37.0°N 6.0°E / 37.0; 6.0 Coordinates: 37°00′N6°00′E / 37.0°N 6.0°E / 37.0; 6.0
Diameter	25 km
Depth	2.8 km
Colongitude	354° at sunrise
Eponym	Theaetetus